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141.
为了提高空间数据质检的效率,实现要素类间拓扑空间关系的智能检测,提出了面向规则的智能空间数据质检模型(RSTT),重点讨论了RSTT模型体系结构和拓扑规则等核心问题.基于RSTT和四层体系结构模型,以空间数据质检方案的灵活定制、数据批量自动检查和质检规则零编码扩展等为目标,开发了空间数据质检系统LR_Checker.通过近40G的国土资源空间数据测试表明,应用LR_Checker进行数据检查可大大降低空间数据建库的工作量,并可有效控制数据质量,同时也证明RSTT模型的正确性、有效性和合理性. 相似文献
142.
Oriented graphs in which every pair of vertices can be connected by a unique path of given length (not depending on the choice
of the pair of vertices) are studied. These graphs are a natural extension of the well-known de Bruijn graphs and retain their
most important properties. Some results on the structure of and methods for constructing such graphs are obtained.
Translated fromMatematicheskie Zametki, Vol. 62, No. 4, pp. 540–548, October, 1997.
Translated by O. V. Sipacheva 相似文献
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Enrico Marchetti Roland Brast Bernard Delabre Rob Donaldson Enrico Fedrigo Christoph Frank Norbert Hubin Johann Kolb Miska Le Louarn Jean-Louis Lizon Sylvain Oberti Fernando Quirs-Pacheco Roland Reiss Joana Santos Sebastien Tordo Elise Vernet Roberto Ragazzoni Carmelo Arcidiacono Paolo Bagnara Andrea Baruffolo Emiliano Diolaiti Jacopo Farinato Matteo Lombini 《Comptes Rendus Physique》2005,6(10):1118-1128
The European Southern Observatory (ESO) together with external research institutes have built a Multi-Conjugate Adaptive Optics (MCAO) Demonstrator (MAD) to perform wide field-of-view adaptive optics correction (2′ in K band). The aim of MAD is to demonstrate the on-sky feasibility of the MCAO technique and to evaluate its critical aspects in the framework of both the 2nd generation instrumentation for the Very Large Telescope (VLT) and the Overwhelmingly Large Telescope (OWL). The MAD module will be installed on the VLT to perform on-sky observations. MAD comprises two deformable mirrors and two different multi-reference wavefront sensors with natural guide stars. In this article we present the MAD design, some aspects of the MAD calibration and the first closed-loop results in the laboratory in Single Conjugated Adaptive Optics (SCAO) and Ground Layer Adaptive Optics (GLAO) configurations. To cite this article: E. Marchetti et al., C. R. Physique 6 (2005). 相似文献
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A procedure is presented for obtaining conformational parameters from oriented but non-crystalline polymers. This is achieved by comparison of the experimental wide angle X-ray scattering with that calculated from models but in such a way that foreknowledge of the orientation distribution function is not required. X-ray scattering intensity values for glassy isotactic poly(methylmethacrylate) are analysed by these techniques. The method could be usefully applied to other oriented molecular systems such as liquid crystalline materials. 相似文献
148.
Microwave enhanced diversity oriented synthesis (MEDOS) of various N- and O-heterocyclic systems fused with 1,3-oxazine ring is reported. The synthesis represents a new montmorillonite K-10 clay-catalyzed green protocol, which utilizes d-glucose/d-xylose as biorenewable feedstocks. d-Glucose/d-xylose-derived 1,3-oxazin-2-ones(thiones) either directly undergo K-10 clay-catalyzed cyclization to yield pyrano-/furo-1,3-oxazine systems under solvent-free microwave irradiation conditions or afford azolo-/azino-1,3-oxazines when subjected to Malaprade reaction followed by cyclization with appropriate reagents, viz. phenylhydrazine, hydroxylamine, acetamidine, phenylurea and semi(thiosemi)carbazide. 相似文献
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